Telephone-receiver.



No. 753,363.' l y PATBNTED APR. 26, 1904.

M. R.; HUTGHISGN.

TELEPHONE RBGBIVBR, APPLIOATION FILED NOV.. 26. 1802.

j No MODEL.

Gmbnooe'o 514mm Afor v UNITED STATns rammed April 2c, 1904;

PATENT Oiuucn.

MESNE ASSIGNMENTS, TO HUTOHISON RATION OF NEW YORK.

ACOUSTIC COMPANY, a vCORPO- TELEPHONE-RECEIVER.

SPECIFICATION forming' part of Letters Patent No. 758,863, dated April A26, 1904.

Application filed November 25, 1902. Serial No. 132,715. (No model.) I

New Jersey, have invented certain new-and useful Improvements in Telephone-Receivers,

, of which the following is a full, clearand exact description.

This invention relates'to telephonic apparatus in which a vibratile diaphragm is used, and has special reference to telephonie` receivers wherein the diaphragm is vibrated by pulsationsof current traversing an electromagnet or magnets whose poles are presented to the diaphragm.

The object of the invention is to provide means whereby any person can adjust the distance between the diaphragm and the polepieces of the magnet for the purpose of tempering or proportioning the intensity of the sound and the distinctness of the speech to the sensitiveness of the ear, the idea being more especially to furnish instruments for the use of deaf persons which can be readily and finely adjusted and any particular degree of adjustment maintained or if lost again easily found. For this purpose my invention consists of a telephone-receiver whose casing is in two parts, one forming the body, in which the magnet or magnets are located, and the other a cover, in which the diaphragm is located. These two parts screw together, and the distance between the diaphragm and magnet poles is determined by the extent to which the cover is screwed over the body of the case. On the cover and case are placed a scale and index, and certain detente are embodied in the construction which tend to lock the case and cover against rotary movement on the points of the scale. The scale may 'cover the entire periphery of the instrument or only a fraction thereof; but its extent will be suiiicient to obtain any adjustment between a required minimum and maximum after the parts have been screwed together tothe point of the average adjustment used.

Further details will be explained with reference tothe accompanying drawings, in Which- Figure l is a side elevation of my improved 'lessness, or tampering.

telephone-receiver. Fig. 2 is a section thereof. Fig. 3 is a plan of one of the ring-nuts that confine the diaphragm, and Fig. 4 is an Y enlarged detail of the locking-bolt.

A is the case or body of a telephone-receiver, and B the cover thereof and adapted to be connected thereto by means of the screwthreads a. Fixed in the center of the case is an electromagnet a', whose poles are presented outward. The cover has an opening at the center for the emission-of sound and carries adiaphragm I), which is held between two clamping rings or nuts b and b2, screwed in on al continuation of the thread a, in the cover. The outer ring Z2 contains a number of shallow sockets b3 equally spaced all around, and facing these are a number of round-headed bolts or pins e, set into sockets c in the rim of the case and resting upon springs c2. There may be any number of these bolts, from one up to the number of the sockets 3; but

they are so placed that all of them will entera socket when any one does.- These bolts and sockets afford a look to prevent relative rotation of the case and cover except by design, a little force being necessary to overcome the frictional engagement of the bolts and sockets.

The periphery of the case is divided into thirty-two or any other desired number of equal parts and a figure or other identifying character applied to each division-mark, as seen at d' in Fig. 1. On the loutside of the case an index e is provided to point to the division-marks of the scale.

When the instrument is assembled for use,`

the cover is screwed down to a point where a half-rotation or less in either direction will position the diaphragm most advantageously for any condition of use. Then by testing the instrument at the ear and moving the cover from point to point in either direction a position is soon found where the sounds or speech are most distinct and comfortable to the listener. The instrument is then in adjustment for that particular person and will remain in adjustment by reason of the locking-bolts unless thrown out by accident, care- The user of theinstrument will, however, be able to make note of the division-mark on the scale to which the index points when the instrument is properly adjusted, and therefore can turn it to that point at once in case it has been moved and without the necessity of'testing.

Having described my invention, I claim- In a telephone-receiver, the combination of a casing in two parts connected togetherl by a screw-thread, a magnet in one part and a dia- IO phragm in the other, a scale on the outside of one part and an inde-X on the other whereby the distance between the pole or poles of the magnet and the diaphragm can be determined by the position of the indeX with respect to the scale, and automatically-acting detents where- I 5 MILLER REESE HUTCHISON.

Witnesses:

FRANK S. OBER, WALDo M. CHAPIN. 

